[2] It has to be at least 1966, but more likely late-60s because in frame 00:39 you can see the logo for "Master Charge" on a store window. Master Charge was created in 1966, but didn't become popular until later in the decade.

Love how, given where current fashion is on the nostalgia/retro curve, most of those folks wouldn't look all that out of place strolling down 8th today. The other random (if obvious) bit that popped into my head was how ubiquitous VW Beetles were even through the 80's vs. how few I see today.